Request For Comments - RFC8101

Internet Engineering Task Force (IETF) C. Holmberg
Request for Comments: 8101 J. Axell
Category: Informational Ericsson
ISSN: 2070-1721 March 2017
IANA Registration of New Session Initiation Protocol (SIP)
Resource-Priority Namespace for Mission Critical Push To Talk Service
Abstract
This document creates additional Session Initiation Protocol (SIP)
Resource-Priority namespaces to meet the requirements of the
3GPP-defined Mission Critical Push To Talk (MCPTT) and places these
namespaces in the corresponding IANA registry.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc8101.
Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved.
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RFC 8101 MCPTT R-P Namespace March 2017
[TS.3GPP.29.214]. The usage of the namespaces can be tailored to the
needs of the operator. The mechanism to do this is to configure
which values a specific user is allowed to use. This configuration
is specified in [TS.3GPP.24.384].
High-priority calls (when the life of either a public safety worker
or anyone else is in danger) need to be set up immediately; thus,
they require preemption. Other calls may be less sensitive in call
setup time but have a high priority once established. For these
calls, a queueing mechanism is more appropriate. The MCPTT data
transfer service currently under development can benefit from a
queueing mechanism. Another example is video-only calls that are not
critical in call setup time but where keeping the call is important.
This document creates additional SIP Resource-Priority namespaces to
meet the requirements of the 3GPP-defined MCPTT and places these
namespaces in the IANA registry.
2. Applicability
This document defines namespaces applicable for MCPTT services
defined by 3GPP that use the network services of a 3GPP-defined LTE
network. The use of this namespace outside such networks is
undefined.
3. New SIP Resource-Priority Namespaces Created
3.1. Introduction
This document introduces the following MCPTT namespaces: mcpttp and
mcpttq. The names of which come from the 3GPP-defined MCPTT service.
3.2. The MCPTT Namespaces
The mcpttp namespace uses the priority levels listed below from
lowest to highest priority.
mcpttp.0 (lowest priority)
mcpttp.1
mcpttp.2
mcpttp.3
mcpttp.4
mcpttp.5
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